"With one voice we are insisting that our government stop managing these beautiful and important animals to extinction," Crow said in a statement released by the Cloud Foundation, a Colorado Springs, Colo.-based horse advocacy group.

Crow, who has adopted a mustang, campaigned for Obama last year. She opposes Salazar's plan to move thousands of wild horses to preserves in the Midwest andEast to protect horse herds and the rangelands that support them.

"It's time for all of us to speak up for our wild horses and burros so we do not lose these living legends and inspiring symbols of our freedom in America," she said.

U.S. Bureau of Land Management officials said they plan to remove 11,500 wild horses and burros from the range over each of the next three years because booming numbers of the animals are damaging the range.

The agency has set a target "appropriate management level" of 26,600 of the animals in the wild, about 10,000 below the current level. An additional 32,000 of them are cared for in government-funded holding facilities.

"Wild horses have an important place on the landscape, but we have to balance that with other uses," BLM spokeswoman Celia Boddington said Saturday. "We have to ensure that the long-term health of the landscape is able to support all these multiple uses."

In a letter sent to Obama and Salazar earlier this week, Crow and actors Ed Harris and Wendie Malick, along with Madeleine Pickens, the wife of oil tycoon T. Boone Pickens, and more than 100 other groups questioned the BLM's horse numbers and said there may be only 15,000 mustangs remaining on public lands.

The BLM has received more than 7,000 public comments concerning its plans to remove 2,500 mustangs near Nevada's Black Rock Desert this winter. Nevada is home to about half of all wild horses.

Salazar has said his plan unveiled last month would avoid the slaughter of some of the 69,000 wild horses and burros under federal control to halt the soaring costs of maintaining them.

The seven preserves would hold about 25,000 horses. Many of the horses remaining on the range would be neutered and reproduction in Western herds would be strictly limited.